Core-breaking drill bit for doubleflute augers



11, 3 o. PHIPPS CORE-BREAKING DRILL BIT FOR DOUBLE-FLUTE AUGERS Filed June 9. 1948 A TTO/PNE) Patented Aug. 11, 1953 CORE -BREAKIN G DRILL BIT FOR DOUBLE- FLUTE AUGERS Orville Phipps, Adams County, 0010.

Application June 9, 1948, Serial No. 31,876

1 Claim. i

This invention is a development from and an improvement over the subject matter of my pending application for United States patent, filed October 29, 1946, Serial No. 706,365, now patent No. 2,578,593, incorporating certain of the teachings of my copending application for United States patent, filed January 6, 1948, Serial No. 681, series of 1948, now abandoned, and has as an object to provide an improved auger-type drill bit susceptible of operative association with and actuation by an auger-type shank or stem of double, spiral flute type.

A further object of the invention is to provide an improved auger-type drill bit adapted for efficient, bore-scavenging cooperation with the helical web terminations of an auger-type drill stem provided with double, spiral flutes.

A further object of the invention is to provide improved core-breaking means in an auger-type drill bit.

A further object of the invention is to provide improved means for operatively and interchangeably associating an auger-type drill bit with the free end of an auger-type actuating stem.

A further object of the invention is to provide an improved auger-type drill bit adapted for the penetration of natural earth beds and strata that is relatively simple and inexpensive of manufacture, susceptible of convenient and repetitious rehabilitation in the field, facile of removal and replacement relative to its actuating means, positive and efiicient in use, and susceptible of practical development in a wide range of sizes adapted to particular and specific uses.

With the foregoing and other objects in View, my invention consists in the construction, arrangement, and combination of elements hereinafter set forth, pointed out in my claim and illustrated by the accompanying drawing, in which-- Figure 1 is a side elevation, partly in section to show otherwise concealed construction and relationships, of a preferred embodiment of the invention as mounted on and for practical association with the end of an auger-type actuating stem. Figure 2 is a view similar to Figure 1 typifying an alternative mounting for the bit element relative to its actuating stem. Figure 3 is a side elevation of the bit shown in Figure 1 as dismounted from its actuating stem and at right angles to the Figure 1 showing. Figure 4 is an outer or working end view of the bit shown in Figure 3. Figure 5 is an inner or attachment end view of the bit according to Figure 3.

In certain types of mining and earth-boring operations, particularly those involving the development of bores at substantial angles to the vertical, it is conventional and wide-spread practice to employ a straight, spirally-fluted stem powered in rotative driving relation with a cutter or bit interchangeably mounted on the free end of the stem, and to rotate said stem for bore-scavenging removal of drillings through the agency of the stem spiral flutes while simultaneously feeding the stem and bit axially against the work for bore extension consequent upon bit rotation and axial advance. Typical bits applicable to use in the manner described are characterized by radially-offset, spaced fingers projecting in substantial parallelism with the associated stem axis, wear-resistant material arming the free or working tips of said fingers, and an axial mounting shank removably and replaceably engageable with the end of an auger stem, and an efiicient, available type of auger stem includes a straight, cylindrical, torque and thrust transmitting core embraced by and constituting the center for double, integrally or fixedly associated, diametrically-opposed, symmetrically and spirally arranged webs or flutes projecting radially therefrom. In the use of such an organization, the bit finger tips cut out an anannular zone from the base or foot of the bore, leaving a central core that must be broken away as an incident of bit rotation to facilitate axial advance of the bit, and the double spiral flutes of the auger stem adequately stifien said stem against deviation and whipping while effectively withdrawing from the bore such cuttings as are fed thereto from and past the bit, hence the instant improvement is directed to the provision of effective core-breaking means and stem-serving, drillings-translating agencies in drill bits of anger type designed for operative association with double-flute auger stems.

In the drawing, a double-flute, bit-actuating, auger stem of the type wherewith the improvements of the instant invention are particularly adapted to be employed is fragmentarily illustrated through a showing of its free end portion wherein the numeral I0 designates the straight, rigid, cylindrical core or center of the stem, which may be either solid or tubular, and the numeral I l designates the diametrically-opposite, symmetrically-arranged, radially-projecting, spiral webs or flutes fixedly entwining the core H] in a characteristic manner. The flutes ll extend to and terminate in the plane of the stem core end wherein they are presented as '3 a relatively narrow radial fingers aligned diametrically of the core, and the end of said core is axially recessed and worked to the form of a coaxial, relatively deep socket adapted to receive and secure the mounting shank of an associated drill bit.

The typical auger-type drill bit interchangeably mountable on and for actuation by the illustrated form \of auger :stem comprises a normally and preferably integral unit of tractable metal including a laterally-expanded .base portion 12 supporting and positioning two or more like cutters or fingers l3 radially offset symmetrically upon and projecting in spaced, generally pan allel relation longitudinally from one side thereof and a mounting shank l4 projecting oppositely to and in parallel relation with :Said ,fingers l3 from the center of the other base side. Radially-outward surfaces of the fingers 13 are worked to cylindrical form in a diameter of orbit slightly exceeding that 10f the *stem 'flutes 1i, whereby :to -.cle.velop .=a :bOI'B wherein :the .stem may rotate and reciprocate Without ibinding, faces \of said :fingers leading :in :thedirection of bit rotation :lie .in :planes iradially of :and including the .bit .axis .of rotation, ,and outer, working end portions ;of said :finger leading faces ,are armed with blocks or :wafers m5 of hard, wear resistant, valloy material inotcheseated andifixed therein with their :margins zbacked :by .:and ground :into rconfonmity with :the adjacent finger material, said blocks rorwvafers :15, in .any rend contour desired, constituting the actual avorkepertorming elements effective to develop ithe iannular cut characteristic of the tool. 3 .and 5,*tl1e mounting shank is :may be worked to angular cross section ior :telesoop o enga ment ivithin acorresponding angularly-sectioned socket opening through :the end of :the stem core 111, :in which case registerable holes Vare provided radially :through the :socket avails and the shank for the reception of a idriveefit dockin :pin it eifeotine when :in place .to hold the :bit :unit to and :against separation axially :from the stem, the angular anterengagement of the shank with its socket uansmitting newer rotation of the stem 112.0 the bit unit without imposing sis-hear stresses .on rthepin :lfi. Alternatively, as represented in FigureZgthe shank Mindy be initially cylindrical and worked to the .sinuous -i l nonebindingscrew thread form disclosed in my copending application .ior patent, Serial No. 16.81, series ;0f c958, end the socket of the stem icerre spondinglyzfurnished'with a mating screw thread, in which event ztheinterenge ement .of :the shank and .socket threads ;is adequate for the transmission of rotational force a -wel-l as to hold the bit :unit against unintended separation from its stem, :it being obvious that v-thelshankiand socket threads :are so pitched 1as fto tighten the joint c mprised therefrom durin work-:performing operation of the assembly.

iGiV-ing efiect to :the principles of the instant invention, :the :tractable metal -..of the fbit base 12 is worked on :the @base side from which the fingers il13 :n oieot to provide an ,arcuately marg-in d ridge :lal bridging diametrically of said base "be tween and alignment with the rotationally leadin races of said fingers, and said ridge is centrally intersected by a slot perpendicular to the ridge margin line and the ,bit axis of rotation onening between and toward the free endsgof the ringers l3 wherein a rectan ular block lskof hard, lweareresistant, alloy material formed witha pyramidal tip 19 is seatedand fixedas by means of welding, brazing. or the like, with its tip 19 As shown in ,Elgures 1,

4 centered on the axis of bit unit rotation and projected away from the base I2 in the same direction as the fingers l3. The tip [9 of the block l8, spaced inwardly from the working ends of the fingers I3, functions to penetrate and break away the core characteristically resulting from operation of the tool, the angular corners of said tip effectively disrupting the core end engaged thereby as the bit rotates ;and axially advances, and the form, location, and position of said tip facilitating the sharpening and reconditioning thereof through simple grinding operations iperformable in the field.

To facilitate and expedite clearance of cuttings from the foot or base of the bore under development-by the tool and to effectively feed said lcuttings :to :the channels between the double flutes of the auger stern for full utilization of the scavenging advantage of the latter, the bit base [2 is formed and worked to provide spiral wings trailing 'the fingers Vi for operative registration with :the terminal fingers of the stem flutes :l I, zthereby, in effect, extending said lflutes through .the bit base. The .spiral wings above noted result from .ashaping of :the bit :base ana- 'terial in va manner to continue the rotationally Lleading facesof :the fingers v4:3 .as iplanes radial of the ;bit axis :through the base l2 :save at the inner end and .side junctions of said faces with the central :zone of :the :base where said faces merge through concave areas into :andw-ithxthe adjacent base central pontion to deeply indent and interrupt the orbital'ly circular outline of the base- ;fipacedlyeopposed, :inner margins .of the fingers ;|;3 define :planes substantiallyperpeniiicular to the associated ringer vleading face and extending :in Width to intersection with the generally eylindrical outer finger surface, thereby def ning a rearwardly-wtapered finger body thickened in the arc of its rotation, and said :finser inner margin planes traverse the length or he [as ociated-finger to the intersection of the rid ill therewith :and :thence merge as...splrallyconcaved, rear-warmly and outwardly directed surfaces with and through the base i2 thickness to intersection'with the opposite .side of said base in substantiall strai ht margins or edges :20 Zapproximately perpendicular to and merging .with the concave :base junctions of the adj acent finger leadin fac the slope of said spirally-conce ned faees'leadin to the edges J19 simulating the pitch and icontourzof the flute l;| radialsurfiaces. 1Comolernentine and :eomple in the operative effiect of the rsoinal-lymone ved bit base surfaces, the radially-extending 'side of the base :lzZ :remote from and lbeenath the fingers :l 3 is outwardly and axially sniraled to slope toward the shank end of the unit from 3401) finger leading face intersection with the base to :mergence in and with the associated trailing tense 251. AS Will the apparent, the edges 20 are designed to operatively register with the terminal fingers of the :stem flutes :H when the bit 215 shank-mounted ion the end of said stem, thereby :to establish continuous spirajhchannels from the throat of the bit to and along thestem,.and such r gistra ion is amatural and invariable consequence of proper cor-relation, fat-the time :of elementzmanuiacture, between the rotationally-interlocking elements, whether screw {threads .or ,angu-larly-related surfaces, ,of the zintercngageable shank and socket members.

The improved bit unit formed, constructed, and arran ed as shown and described functions in mounted association with a power-rotated,

double-flute drill stem to develop and extend a bore with enhanced facility and efficiency. The

armed tips of the fingers 13 cut out the customary annular zone at the foot or base of the bore and the spirally-concaved areas trailing the finger bases feed the cuttings directly and immediately to the spiral scavenging channels of the stem to fully and effectively clear the bit working area and obviate any hampering congestion which might retard cutting action, while the tip I9 of the block 18' rapidly and efficiently disintegrates the end of the core produced centrally of said annular zone, breaking the fragments of said core into the scavenging channels for prompt evacuation from the bore.

Since many changes, variations, and modifications in the specific form, construction, and arrangement of the elements shown and described may be had without departing from the spirit of my invention, I wish to be understood as being limited solely by the scope of the appended claim, rather than by any details of the illustrative showing and foregoing description.

I claim as my invention:

In an auger-type drill bit having a body of tractable metal formed with angularly-spaced, radially-offset, like fingers outstanding in spaced parallelism of their inner side margins with its axis for generation of an annular trough cut as an incident of body rotation, means rotatable with said body to disrupt the core of material centrally of said trough cut, said means comprising a pyramidal block of alloy material formed 6 with a rectangular base portion, an axially-open ing slot diametrically of said body between said fingers for the fitted reception of said block base portion, whereby to mount said pyramidal block as a coaxial projection from said body spacedly adjacent and between the body-fixed ends of said fingers, and a permanent bond uniting engaged surfaces of said slot and block base portion.

ORVILLE PHIPPS.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 218,374 Fishburn Aug. 12, 1879 756,339 Down Apr. 5, 1904 932,071 Urbscheit Aug. 24, 1909 1,387,733 Midgett Aug. 16, 1921 1,403,711 Schaefer et al. Jan. 17, 1922 1,461,548 West July 10, 1923 2,239,461 Mann Apr. 22, 1941 2,339,104 Phipps Jan. 11, 1944 2,461,305 Winn Feb. 8, 1949 FOREIGN PATENTS Number Country Date 351,337 Great Britain June 25, 1931 500,147 Great Britain Feb. 3, 1939 528,593 Great Britain Nov. 1, 1940 592,087 Great Britain Sept. 8, 1947 599,451 Great Britain Mar. 12, 1948 

